JPH0563632B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a multi-cylinder rotary compressor, and particularly to a multi-cylinder rotary compressor that constitutes a refrigeration cycle such as an air conditioner and has a plurality of compression chambers. This relates to a rotary compressor.

[Conventional technology]

In refrigeration cycles that have a large capacity or have multiple stages of compression and expansion processes, multiple compressors are required to compress the refrigerant.

However, it is rare that a plurality of compressors are actually used, and in most cases, a plurality of cylinder compressors each having a plurality of compression chambers are used. The reason for this is that compared to using multiple compressors, a multi-cylinder compressor is (1) cheaper, (2) requires less installation space and can be made more compact, and (3) This is due to the advantage that there is no problem with the balance of the refrigerating machine oil since there is only one chamber for storing the refrigerating machine oil.

As described above, the mainstream of multi-cylinder compressors with high existential value is currently the reciprocating type (that is, multi-cylinder reciprocating compressors), and multi-cylinder rotary compressors are difficult to realize with current manufacturing technology. The reality is that it is still in the development stage and has not yet appeared on the market.

If a multi-cylinder rotary compressor is put into practical use, it will (1) have superior compression performance, (2) have fewer parts, so the cost will be lower, (3) compared to the multi-cylinder reciprocating compressor. It has the advantage of being compact.

The present inventors have already developed a multi-cylinder rotary compressor that can be manufactured using conventional manufacturing techniques, and have filed an application as per Japanese Patent Application No. 11015-1983 (filed on January 28, 1981). .

The characteristics of the multi-cylinder rotary compressor that the present inventors developed earlier are that the chamber includes one motor, at least a cylinder, a roller that rotates eccentrically within the cylinder, and a crank that rotates the roller eccentrically. A shaft, a plurality of compression elements consisting of upper and lower bearings that support the crankshaft, close both end faces of the cylinder, and together with the cylinder constitute a compression chamber are connected and housed in a row, and the most A nearby compression element was directly connected to the motor and fixed to the chamber.

FIG. 4 is a sectional view showing an example of a multiple cylinder rotary compressor previously developed by the present inventors, FIG. 5 is a perspective view showing details of the upper and lower cranks in FIG. 4, and FIG. This figure is a cross-sectional view showing the engaged state of the joints provided on the upper crank and lower crank of FIG. 5.

In FIG. 4, 1 is a chamber, 2a is a chamber upper cover, and 2b is a chamber lower cover, which form a high-pressure pressure chamber. The cylinder is divided into an upper cylinder 26a and a lower cylinder 26b. The upper compression element 3a near the motor includes the upper cylinder 26a, an upper roller 5a that rotates eccentrically within the upper cylinder 26a, and an upper compression element 3a that is connected to the crankshaft directly connected to the motor shaft of the motor that rotates the upper roller 5a eccentrically. Crank 6a (in this example,
The motor shaft and the upper crank 6a are integrated), and are composed of an upper cylinder upper bearing 28a and an upper cylinder lower bearing 27a, which support the upper crank 6a and together with the upper cylinder 26a constitute an upper compression chamber 16a. .

On the other hand, the lower compression element 3b located below the upper compression element 3a receives power from the lower cylinder 26b, the lower roller 5b that rotates eccentrically within the lower cylinder 26b, and the upper crank 6a. (described later), a lower crank 6b related to the crankshaft that eccentrically rotates the lower roller 5b, and a lower cylinder 2 that supports this lower crank 6b.
6b, the lower cylinder upper bearing 28b and the lower cylinder lower bearing 27b constitute the lower compression chamber 16b.

Then, the motor, the upper compression element 3a, and the lower compression element 3b are connected and housed in the chamber 1 (the means of connection will be described later), and the upper cylinder 26a of the upper compression element 3a is connected to the chamber 1. Fixed.

The connection between the upper compression element 3a and the lower compression element 3b is as follows:
An upper bearing 28b for the lower cylinder is fixed to the lower bearing 27a for the upper cylinder with a bolt 29.

Further, the means for transmitting power from the upper compression element 3a to the lower compression element 3b is as shown in FIGS. 5 and 6.

In other words, the crankshaft is connected to the motor shaft 1
0, an upper eccentric part 7 that eccentrically moves the upper roller 5a;
and a concave joint 9 that engages with the convex joint 9a.
b, a lower eccentric part 8 that eccentrically moves the lower roller 5b;
and a lower crank 6b which is integrally molded with the shaft 13.

A roller 11 is fixed to a motor shaft 10 that is integrated with the upper crank 6a.
rotates the upper crank 6a.

Further, 17 is a stator core fitted into the chamber 1, and 18 is a coil.

The multi-cylinder coterie compressor 3 configured in this manner can be manufactured with conventional machining accuracy for the following reasons.

That is, the upper cylinder 26a, the upper roller 5a, and the motor shaft 1 constituting the upper compression element 3a.
The construction and assembly of the upper crank 6a to which the motor rotor 11 is fixed at 0, the upper bearing 28a for the upper cylinder, and the lower bearing 27a for the upper cylinder are no different from those of a conventional single cylinder rotary compressor.

Similarly, the work and assembly of the lower cylinder 26b, lower roller 5b, lower crank 6b, lower cylinder upper bearing 28b, and lower cylinder lower bearing 27b that constitute the lower compression element 3b is different from that of the above-mentioned upper compression element 3a. The work is done independently, and the precision of the work remains the same.

The upper cylinder lower bearing 27a of the upper compression element 3a assembled in this way and the lower compression element 3b
Lower cylinder upper bearing 28b and bolt 2
Tighten and connect at 9. At this time, upper crank 6
As described above, the power is transmitted from a to the lower crank 6b by a combination of the joints 9a and 9b, so that machining accuracy can be improved at the joint between the upper and lower cranks 6a and 6b. Since the machining accuracy of each compression element 3a, 3b is much higher than that of the joints 9a, 9b, it is an extremely effective means to reduce the machining accuracy at the joint portion.

[Problem to be solved by the invention]

By the way, the multi-cylinder rotary compressor previously developed by the present inventors has the following points that should be further improved.

That is, since there is no space between adjacent compression elements, it has not been possible to provide a discharge valve between the two compression elements.

Therefore, when connecting two compression elements, the fourth
As is clear from the figure, the lower discharge valve 21b of the lower compression element 3b needs to be provided on the lower end surface, that is, the lower cylinder lower bearing 27b. In this case, in order to prevent the gas refrigerant discharged from the lower discharge valve 21b from foaming the refrigerating machine oil for lubrication accumulated in the lower part of the chamber 1, the refrigerant gas is transferred to a discharge outlet attached to the lower bearing 27b for the lower cylinder. Since the discharge was once carried out into the discharge chamber 24 formed by the cap 23 and the lower bearing 27b for the lower cylinder, and then upwardly through the discharge passage 25 bored in the lower cylinder 26b and the upper cylinder 26a, multiple cylinders were discharged. The number of parts for rotary compressors has increased,
There was a problem of high processing costs.

Furthermore, for example, when three or more compression elements are connected, the discharge valve of the lowest compression element is provided on the lower end surface, which causes the same problem as described above. The discharge valve of the intermediate compression element must be provided on the side of the cylinder, but in this case, there is a risk of lower volumetric efficiency and overcompression due to the structural constraint of avoiding vanes.

The present invention further improves the multi-cylinder rotary compressor previously developed by the present inventors, and achieves a low cost, no reduction in volumetric efficiency, no overcompression, and further improves compressed gas discharge. The object of the present invention is to provide a multi-cylinder rotary compressor that can reduce noise during operation.

[Means to solve the problem]

In order to achieve the above object, the configuration of the multiple cylinder rotary compressor according to the present invention includes one motor in the chamber, and a motor directly connected to the motor.
It houses multiple compression elements that compress refrigerant gas,
The plurality of compression elements include at least a cylinder,
A multi-cylinder rotary compressor consisting of a roller that rotates eccentrically within this cylinder, a crankshaft that rotates this roller eccentrically, and a bearing that supports this crankshaft and closes both end faces of the cylinder and forms a compression chamber with the cylinder. In,
A discharge chamber is provided between mutually adjacent compression elements, and the discharge chamber is configured to discharge gas refrigerant from one of the two adjacent compression elements, and the discharge chamber and the other suction passage of both compression elements are connected to each other. A communication passage for connection is provided.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 3.

FIG. 1 is a sectional view of a multiple cylinder rotary compressor according to an embodiment of the present invention, FIG. 2 is a perspective view showing details around the upper and lower cylinders in FIG. 1, and FIG. 1 is a cycle configuration diagram showing an example of a refrigeration cycle incorporating the multiple cylinder rotary compressor according to FIG. 1. FIG.

In this FIG. 1, parts given the same reference numerals as in FIG. 4 are the same parts.

Multiple cylinder rotary compressor 39 of this embodiment
However, the difference from the multi-cylinder rotary compressor 3 shown in FIG. 4 described above is the lower bearing 27c for the upper cylinder and the upper bearing 28 for the lower cylinder.
d, an inter-cylinder discharge chamber 32 related to the discharge chamber for the lower compression element 33b is provided, a lower discharge valve 21b is provided in this inter-cylinder discharge chamber 32, and the inter-cylinder discharge chamber 32 and the upper suction passage 31a are connected to each other. Communication path 3 connecting
8 was established. The upper discharge valve 21a is provided on the upper cylinder upper bearing 28C.

Details around the upper cylinder 26c and lower cylinder 26d will be explained with reference to FIG.

In FIG. 2, 26c is an upper cylinder, and an upper cylinder upper bearing 28c and an upper cylinder lower bearing 27c are fixed to this upper cylinder 26c with fixing bolts 36 (the lower bearing side is in a position not shown). A motor shaft 34 integrally formed with the upper crank 6a (see FIG. 1) is supported by the upper and lower bearings 28c and 27c.

26d is a lower cylinder; this lower cylinder 26d
, a cup-shaped upper bearing for the lower cylinder 28d and a lower bearing for the lower cylinder 27d.
is fixed with a locking bolt 36 (the lower bearing side is in a position not shown). 30a, 30
b are the upper compression element 39a and the lower compression element 3, respectively.
9b, these suction pipes 30a,
30b, upper suction passage 31a, lower suction passage 31
b is provided. In addition, 35a and 35b are
These are uneven joints that are integrally molded with the upper crank 6a and the lower crank 6b, respectively.

The lower bearing 27c for the upper cylinder and the upper bearing 28d for the lower cylinder are connected by bolts 29 (see Fig. 1), but as mentioned above, the upper bearing 28d for the lower cylinder is formed into a cup shape. , lower bearing 27c for upper cylinder
A space, ie, an inter-cylinder discharge chamber 32, can be provided between the upper bearing 28d and the lower cylinder upper bearing 28d. A lower discharge valve 21b is arranged in this inter-cylinder discharge chamber 32.

The flow of refrigerant in the multi-cylinder rotary compressor 39 configured as described above is as follows.

The refrigerant sucked from the lower cylinder suction pipe 30b passes through the lower suction passage 31b and enters the lower compression chamber 16b.
After being compressed, the inter-cylinder discharge chamber 3 formed by the lower bearing 27c for the upper cylinder and the upper bearing 28d for the lower cylinder is discharged from the lower discharge valve 21b.
2. Next, the communication passage 3 provided between the lower bearing 27c for the upper cylinder and the upper cylinder 26c.
8, the refrigerant enters the upper compression chamber 16a from the upper suction passage 31a together with the refrigerant sucked from the upper cylinder suction pipe 30a, and after being compressed, it passes through the upper discharge valve 21a and is discharged from the discharge pipe 22 to the outside of the compressor. Ru.

Therefore, the discharge cap 2 required in the multiple cylinder rotary compressor 3 shown in FIG.
3 is unnecessary, and there is no need to drill a discharge passage in the lower cylinder 26d, resulting in cost reduction.

In addition, the discharged gas does not bubble up the lubricating refrigerating machine oil in the chamber 1, and proper lubrication performance is ensured.

Furthermore, the space of the inter-cylinder discharge chamber 32 functions as a silencer by damping when compressed gas is discharged, and can reduce the pulsating noise of the discharged gas. Sound insulation.

An example of a refrigeration cycle incorporating this multi-cylinder rotary compressor 39 will be described with reference to FIG. 3.

In FIG. 3, 39a is an upper compression element, 39b
is a lower compression element, 40 is an evaporator, 41 is a condenser, 4
2 is a first pressure reducer, 43 is a gas-liquid separator, and 44 is a second pressure reducer.
It is a pressure reducer.

To explain the flow of refrigeration, the high-pressure gas refrigerant discharged from the discharge pipe 22 is condensed in the condenser 41 and becomes liquid refrigerant. Next, the first pressure reducer 42 reduces the pressure to an intermediate pressure, resulting in a two-phase state, and the gas-liquid separator 43 separates the refrigerant into gas refrigerant and liquid refrigerant. The gas refrigerant passes through the upper suction pipe 30a and is led directly to the upper compression element 39a of the multi-cylinder rotary compressor 39, while the liquid refrigerant is further reduced in pressure in the second pressure reducer 44 and evaporated in the evaporator 40. After passing through the lower suction pipe 30b and being compressed by the lower compression element 39b, it is guided through the communication path 38 to the upper compression element 39a.

The above-mentioned refrigeration cycle is called a multi-effect cycle, and in the present embodiment, one multi-cylinder rotary compressor 39 is used instead of the one that was conventionally put into practical use with two independent compressors. This will be achieved.

In addition, although the above-mentioned Example demonstrated the case where there were two compression elements, this invention is similarly applicable to the case where three or more compression elements are connected. If applied to the case of three or more cylinders, there is no need to provide a discharge valve on the side of the cylinder, so problems such as a decrease in volumetric efficiency and overcompression do not occur.

Further, in the above embodiment, the upper bearing 28d for the lower cylinder is formed into a cup shape to provide a space between the upper and lower compression elements 33a, 33b, but the upper cylinder 26c, the lower bearing 27c for the upper cylinder, The lower cylinders 26d may each be formed into a cup shape, or separate parts may be used to provide a space between the compression elements.

Further, in each of the above embodiments, a concave-convex joint is used for the joint portions of the upper and lower cranks, but the joint is not limited to a concave-convex joint, and a spline-type joint or other means may also be used. .

〔Effect of the invention〕

As explained in detail above, according to the present invention,
A discharge chamber for one of the compression elements is provided between adjacent compression elements, and a communication path is provided to connect the discharge compression chamber to the suction passage of the other compression element, so the cost is low and reduction in volumetric efficiency,
To provide a multi-cylinder rotary compressor that does not cause overcompression and can reduce noise when discharging compressed gas because the space in the discharge chamber functions as a silencer and is sound-insulated by a compression element. I can do it.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a multiple cylinder rotary compressor according to an embodiment of the present invention, FIG. 2 is a perspective view showing details around the upper and lower cylinders in FIG. 1, and FIG. FIG. 1 is a cycle configuration diagram showing an example of a refrigeration cycle incorporating a multiple cylinder rotary compressor, and FIG. 4 is a cross section showing an example of a multiple cylinder rotary compressor previously developed by the present inventors. Fig. 5 is a perspective view showing details of the upper crank and lower crank in Fig. 4, and Fig. 6 is a sectional view showing the engaged state of the joints provided on the upper crank and lower crank in Fig. 5. be. 1...Chamber, 5a...Upper roller, 5b...
Lower roller, 6a... Upper crank, 6b... Lower crank, 11... Rotor, 16a... Upper compression chamber, 1
6b...Lower compression chamber, 17...Stator core, 18
...Coil, 26c...Upper cylinder, 26d...
Lower cylinder, 27c...Lower bearing for upper cylinder, 27d...Lower bearing for lower cylinder, 28
c...Upper bearing for upper cylinder, 28d...Upper bearing for lower cylinder, 32...Discharge chamber between cylinders, 38...Communication path, 39...Multi-cylinder rotary compressor, 39a...Upper compression element, 39b
... lower compression element, 35 ... convex joint, 35b ...
Concave fitting.

Claims (1)

[Claims] 1. A motor and a plurality of compression elements that compress refrigerant gas are housed in a chamber, and the plurality of compression elements are connected to at least a cylinder, a cylinder, and a plurality of compression elements that compress refrigerant gas. In a multi-cylinder rotary compressor consisting of a roller that rotates eccentrically within a cylinder, a crankshaft that rotates the roller eccentrically, and a bearing that supports the crankshaft and closes both end faces of the cylinder and forms a compressible mass with the cylinder. , a discharge chamber is provided between mutually adjacent compression elements, and the gas refrigerant of one of the two adjacent compression elements is discharged from the discharge chamber, and the discharge chamber and the suction passage of the other of the two compression elements are connected to each other. A multiple cylinder rotary compressor characterized by having a communication passage connecting the two.